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Strong correlation between the pre‐breakdown sites visible in dark lock‐in thermography due to local heating and the intensity of spatially resolved electroluminescence of reverse‐biased solar cells was observed. By comparing differently texturised solar cells we could show that the pre‐breakdown sites are not correlated to the surface morphology, e.g. etch pits resulting in local field enhancement. The positions of the pre‐breakdown sites are identical for acidic and alkaline texturised solar cells and therefore are directly related to bulk defects in the wafer. Nevertheless, the breakdown voltage is lower for acidic texturised solar cells; the parameters of breakdown are influenced by the texture in contrast to the position. Also pre‐breakdown sites are observed in areas without specific surface features for alkaline texturised solar cells. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

We have investigated the formation of large-grained polycrystalline silicon (poly-Si) films on glass for thin-film solar cells using the 'seed layer concept' which is based on the epitaxial thickening of a thin large-grained poly-Si template (seed layer). Due to the glass substrate all

The local breakdown of commercial silicon solar cells occurring at reverse voltages of only 3-4 V has been investigated by means of current-voltage measurements, dark lock-in thermography, and reverse-biased electroluminescence (ReBEL) with a spatial resolution on the micrometer-scale. It is shown that the origin of the local breakdown (so-called type I) can be traced back to a contamination of the wafer surface with Al particles prior to the phosphorous diffusion step. A model is presented explaining that the spectral maximum of ReBEL is within the visible range